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			<h1>Python 面向对象</h1>
<div class="tutintro">
<p>
Python从设计之初就已经是一门面向对象的语言，正因为如此，在Python中创建一个类和对象是很容易的。本章节我们将详细介绍Python的面向对象编程。
</p>
<p>
如果你以前没有接触过面向对象的编程语言，那你可能需要先了解一些面向对象语言的一些基本特征，在头脑里头形成一个基本的面向对象的概念，这样有助于你更容易的学习Python的面向对象编程。
</p>
<p>
接下来我们先来简单的了解下面向对象的一些基本特征。
</p>

</div>

<hr>
<h2>面向对象技术简介</h2>
<ul>
<li><strong>类(Class): </strong>用来描述具有相同的属性和方法的对象的集合。它定义了该集合中每个对象所共有的属性和方法。对象是类的实例。</li>
<li><strong>类变量：</strong>类变量在整个实例化的对象中是公用的。类变量定义在类中且在函数体之外。类变量通常不作为实例变量使用。</li>
<li><strong>数据成员：</strong>类变量或者实例变量, 用于处理类及其实例对象的相关的数据。</li>
<li><strong>方法重写：</strong>如果从父类继承的方法不能满足子类的需求，可以对其进行改写，这个过程叫方法的覆盖（override），也称为方法的重写。</li>
<li><strong>局部变量：</strong>定义在方法中的变量，只作用于当前实例的类。</li>
<li><strong>实例变量：</strong>在类的声明中，属性是用变量来表示的。这种变量就称为实例变量，是在类声明的内部但是在类的其他成员方法之外声明的。</li>
<li><strong>继承：</strong>即一个派生类（derived class）继承基类（base class）的字段和方法。继承也允许把一个派生类的对象作为一个基类对象对待。例如，有这样一个设计：一个Dog类型的对象派生自Animal类，这是模拟"是一个（is-a）"关系（例图，Dog是一个Animal）。</li>
<li><strong>实例化：</strong>创建一个类的实例，类的具体对象。</li>
<li><strong>方法：</strong>类中定义的函数。</li>
<li><strong>对象：</strong>通过类定义的数据结构实例。对象包括两个数据成员（类变量和实例变量）和方法。</li>
</ul>
<hr>
<h2>创建类</h2>

<p>
使用 class 语句来创建一个新类，class 之后为类的名称并以冒号结尾:</p>
<pre>
class ClassName:
   '类的帮助信息'   #类文档字符串
   class_suite  #类体
</pre>
<p>类的帮助信息可以通过ClassName.__doc__查看。</p>
<p>
class_suite 由类成员，方法，数据属性组成。</p>

<h3>实例</h3>
<p>
以下是一个简单的 Python 类的例子:</p>
<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">#!/usr/bin/python</span><span class="hl-code">
</span><span class="hl-comment"># -*- coding: UTF-8 -*-</span><span class="hl-code">
 
</span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Employee</span><span class="hl-code">:
   </span><span class="hl-quotes">'</span><span class="hl-string">所有员工的基类</span><span class="hl-quotes">'</span><span class="hl-code">
   </span><span class="hl-identifier">empCount</span><span class="hl-code"> = </span><span class="hl-number">0</span><span class="hl-code">
 
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">__init__</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-code">, </span><span class="hl-identifier">name</span><span class="hl-code">, </span><span class="hl-identifier">salary</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">name</span><span class="hl-code"> = </span><span class="hl-identifier">name</span><span class="hl-code">
      </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">salary</span><span class="hl-code"> = </span><span class="hl-identifier">salary</span><span class="hl-code">
      </span><span class="hl-identifier">Employee</span><span class="hl-code">.</span><span class="hl-identifier">empCount</span><span class="hl-code"> += </span><span class="hl-number">1</span><span class="hl-code">
   
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">displayCount</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
     </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">Total Employee %d</span><span class="hl-quotes">&quot;</span><span class="hl-code"> % </span><span class="hl-identifier">Employee</span><span class="hl-code">.</span><span class="hl-identifier">empCount</span><span class="hl-code">
 
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">displayEmployee</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">Name : </span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">name</span><span class="hl-code">,  </span><span class="hl-quotes">&quot;</span><span class="hl-string">, Salary: </span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">salary</span></div>
</div>
</div>
<ul>
<li><p>empCount 变量是一个类变量，它的值将在这个类的所有实例之间共享。你可以在内部类或外部类使用 Employee.empCount 访问。</p></li>
<li><p>第一种方法__init__()方法是一种特殊的方法，被称为类的构造函数或初始化方法，当创建了这个类的实例时就会调用该方法</p></li>	
<li><p>self 代表类的实例，self 在定义类的方法时是必须有的，虽然在调用时不必传入相应的参数。</p></li>
</ul>
<h3>self代表类的实例，而非类</h3>
<p>类的方法与普通的函数只有一个特别的区别——它们必须有一个额外的<strong>第一个参数名称</strong>, 按照惯例它的名称是 self。</p>
<div class="example"> 
<div class="example_code">
<div class="hl-main"><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Test</span><span class="hl-code">:
    </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">prt</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
        </span><span class="hl-identifier">print</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">
        </span><span class="hl-identifier">print</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">__class__</span><span class="hl-brackets">)</span><span class="hl-code">
 
</span><span class="hl-identifier">t</span><span class="hl-code"> = </span><span class="hl-identifier">Test</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">
</span><span class="hl-identifier">t</span><span class="hl-code">.</span><span class="hl-identifier">prt</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span></div>
</div>
</div>
<p>以上实例执行结果为：</p>
<pre>
&lt;__main__.Test instance at 0x10d066878&gt;
__main__.Test
</pre>
<p>从执行结果可以很明显的看出，self 代表的是类的实例，代表当前对象的地址，而 <span class="marked">self.__class__</span> 则指向类。</p>
<p>self 不是 python 关键字，我们把他换成 runoob 也是可以正常执行的:</p>

<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Test</span><span class="hl-code">:
    </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">prt</span><span class="hl-brackets">(</span><span class="hl-identifier">runoob</span><span class="hl-brackets">)</span><span class="hl-code">:
        </span><span class="hl-identifier">print</span><span class="hl-brackets">(</span><span class="hl-identifier">runoob</span><span class="hl-brackets">)</span><span class="hl-code">
        </span><span class="hl-identifier">print</span><span class="hl-brackets">(</span><span class="hl-identifier">runoob</span><span class="hl-code">.</span><span class="hl-identifier">__class__</span><span class="hl-brackets">)</span><span class="hl-code">
 
</span><span class="hl-identifier">t</span><span class="hl-code"> = </span><span class="hl-identifier">Test</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">
</span><span class="hl-identifier">t</span><span class="hl-code">.</span><span class="hl-identifier">prt</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span></div>
</div>
</div><p>以上实例执行结果为：</p>
<pre>
&lt;__main__.Test instance at 0x10d066878&gt;
__main__.Test
</pre>
<hr><h2>创建实例对象</h2>
<p>实例化类其他编程语言中一般用关键字 new，但是在 Python 中并没有这个关键字，类的实例化类似函数调用方式。</p>
<p>
以下使用类的名称 Employee 来实例化，并通过 __init__ 方法接收参数。</p>
<pre>
"创建 Employee 类的第一个对象"
emp1 = Employee("Zara", 2000)
"创建 Employee 类的第二个对象"
emp2 = Employee("Manni", 5000)
</pre>

<h2>访问属性</h2>
<p>您可以使用点号 <span class="marked">.</span> 来访问对象的属性。使用如下类的名称访问类变量:</p>
<pre>
emp1.displayEmployee()
emp2.displayEmployee()
print "Total Employee %d" % Employee.empCount
</pre>
<p>完整实例：</p>
<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">#!/usr/bin/python</span><span class="hl-code">
</span><span class="hl-comment"># -*- coding: UTF-8 -*-</span><span class="hl-code">
 
</span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Employee</span><span class="hl-code">:
   </span><span class="hl-quotes">'</span><span class="hl-string">所有员工的基类</span><span class="hl-quotes">'</span><span class="hl-code">
   </span><span class="hl-identifier">empCount</span><span class="hl-code"> = </span><span class="hl-number">0</span><span class="hl-code">
 
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">__init__</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-code">, </span><span class="hl-identifier">name</span><span class="hl-code">, </span><span class="hl-identifier">salary</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">name</span><span class="hl-code"> = </span><span class="hl-identifier">name</span><span class="hl-code">
      </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">salary</span><span class="hl-code"> = </span><span class="hl-identifier">salary</span><span class="hl-code">
      </span><span class="hl-identifier">Employee</span><span class="hl-code">.</span><span class="hl-identifier">empCount</span><span class="hl-code"> += </span><span class="hl-number">1</span><span class="hl-code">
   
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">displayCount</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
     </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">Total Employee %d</span><span class="hl-quotes">&quot;</span><span class="hl-code"> % </span><span class="hl-identifier">Employee</span><span class="hl-code">.</span><span class="hl-identifier">empCount</span><span class="hl-code">
 
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">displayEmployee</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">Name : </span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">name</span><span class="hl-code">,  </span><span class="hl-quotes">&quot;</span><span class="hl-string">, Salary: </span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">salary</span><span class="hl-code">
 
</span><span class="hl-quotes">&quot;</span><span class="hl-string">创建 Employee 类的第一个对象</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-identifier">emp1</span><span class="hl-code"> = </span><span class="hl-identifier">Employee</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">Zara</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-number">2000</span><span class="hl-brackets">)</span><span class="hl-code">
</span><span class="hl-quotes">&quot;</span><span class="hl-string">创建 Employee 类的第二个对象</span><span class="hl-quotes">&quot;</span><span class="hl-code">
</span><span class="hl-identifier">emp2</span><span class="hl-code"> = </span><span class="hl-identifier">Employee</span><span class="hl-brackets">(</span><span class="hl-quotes">&quot;</span><span class="hl-string">Manni</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-number">5000</span><span class="hl-brackets">)</span><span class="hl-code">
</span><span class="hl-identifier">emp1</span><span class="hl-code">.</span><span class="hl-identifier">displayEmployee</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">
</span><span class="hl-identifier">emp2</span><span class="hl-code">.</span><span class="hl-identifier">displayEmployee</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">Total Employee %d</span><span class="hl-quotes">&quot;</span><span class="hl-code"> % </span><span class="hl-identifier">Employee</span><span class="hl-code">.</span><span class="hl-identifier">empCount</span></div>
</div>
</div>
<p>执行以上代码输出结果如下：</p>
<pre>
Name :  Zara ,Salary:  2000
Name :  Manni ,Salary:  5000
Total Employee 2
</pre>
<p>你可以添加，删除，修改类的属性，如下所示：</p>
<pre>
emp1.age = 7  # 添加一个 'age' 属性
emp1.age = 8  # 修改 'age' 属性
del emp1.age  # 删除 'age' 属性
</pre>
<p>你也可以使用以下函数的方式来访问属性：</p>
<ul>
<li>getattr(obj, name[, default]) : 访问对象的属性。</li>
<li>hasattr(obj,name) : 检查是否存在一个属性。</li>
<li>setattr(obj,name,value) : 设置一个属性。如果属性不存在，会创建一个新属性。</li>
<li>delattr(obj, name) : 删除属性。</li>
</ul>
<div class="example">
<div class="example_code">
<div class="hl-main"><span class="hl-builtin">hasattr</span><span class="hl-brackets">(</span><span class="hl-identifier">emp1</span><span class="hl-code">, </span><span class="hl-quotes">'</span><span class="hl-string">age</span><span class="hl-quotes">'</span><span class="hl-brackets">)</span><span class="hl-code">    </span><span class="hl-comment"># 如果存在 'age' 属性返回 True。</span><span class="hl-code">
</span><span class="hl-builtin">getattr</span><span class="hl-brackets">(</span><span class="hl-identifier">emp1</span><span class="hl-code">, </span><span class="hl-quotes">'</span><span class="hl-string">age</span><span class="hl-quotes">'</span><span class="hl-brackets">)</span><span class="hl-code">    </span><span class="hl-comment"># 返回 'age' 属性的值</span><span class="hl-code">
</span><span class="hl-builtin">setattr</span><span class="hl-brackets">(</span><span class="hl-identifier">emp1</span><span class="hl-code">, </span><span class="hl-quotes">'</span><span class="hl-string">age</span><span class="hl-quotes">'</span><span class="hl-code">, </span><span class="hl-number">8</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-comment"># 添加属性 'age' 值为 8</span><span class="hl-code">
</span><span class="hl-builtin">delattr</span><span class="hl-brackets">(</span><span class="hl-identifier">emp1</span><span class="hl-code">, </span><span class="hl-quotes">'</span><span class="hl-string">age</span><span class="hl-quotes">'</span><span class="hl-brackets">)</span><span class="hl-code">    </span><span class="hl-comment"># 删除属性 'age'</span></div>
</div>
</div>
<hr>
<h2>Python内置类属性</h2>
<ul>
<li>__dict__ : 类的属性（包含一个字典，由类的数据属性组成） </li>
<li>__doc__ :类的文档字符串 </li>
<li>__name__: 类名 </li>
<li>__module__:   类定义所在的模块（类的全名是'__main__.className'，如果类位于一个导入模块mymod中，那么className.__module__ 等于 mymod） </li>
<li>__bases__ : 类的所有父类构成元素（包含了一个由所有父类组成的元组） </li>
</ul>
<p>Python内置类属性调用实例如下：</p>
<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">#!/usr/bin/python</span><span class="hl-code">
</span><span class="hl-comment"># -*- coding: UTF-8 -*-</span><span class="hl-code">
 
</span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Employee</span><span class="hl-code">:
   </span><span class="hl-quotes">'</span><span class="hl-string">所有员工的基类</span><span class="hl-quotes">'</span><span class="hl-code">
   </span><span class="hl-identifier">empCount</span><span class="hl-code"> = </span><span class="hl-number">0</span><span class="hl-code">
 
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">__init__</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-code">, </span><span class="hl-identifier">name</span><span class="hl-code">, </span><span class="hl-identifier">salary</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">name</span><span class="hl-code"> = </span><span class="hl-identifier">name</span><span class="hl-code">
      </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">salary</span><span class="hl-code"> = </span><span class="hl-identifier">salary</span><span class="hl-code">
      </span><span class="hl-identifier">Employee</span><span class="hl-code">.</span><span class="hl-identifier">empCount</span><span class="hl-code"> += </span><span class="hl-number">1</span><span class="hl-code">
   
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">displayCount</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
     </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">Total Employee %d</span><span class="hl-quotes">&quot;</span><span class="hl-code"> % </span><span class="hl-identifier">Employee</span><span class="hl-code">.</span><span class="hl-identifier">empCount</span><span class="hl-code">
 
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">displayEmployee</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">Name : </span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">name</span><span class="hl-code">,  </span><span class="hl-quotes">&quot;</span><span class="hl-string">, Salary: </span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">salary</span><span class="hl-code">
 
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">Employee.__doc__:</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">Employee</span><span class="hl-code">.</span><span class="hl-identifier">__doc__</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">Employee.__name__:</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">Employee</span><span class="hl-code">.</span><span class="hl-identifier">__name__</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">Employee.__module__:</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">Employee</span><span class="hl-code">.</span><span class="hl-identifier">__module__</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">Employee.__bases__:</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">Employee</span><span class="hl-code">.</span><span class="hl-identifier">__bases__</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">Employee.__dict__:</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">Employee</span><span class="hl-code">.</span><span class="hl-identifier">__dict__</span></div>
</div>
</div>
<p>执行以上代码输出结果如下：</p>
<pre>
Employee.__doc__: 所有员工的基类
Employee.__name__: Employee
Employee.__module__: __main__
Employee.__bases__: ()
Employee.__dict__: {'__module__': '__main__', 'displayCount': &lt;function displayCount at 0x10a939c80&gt;, 'empCount': 0, 'displayEmployee': &lt;function displayEmployee at 0x10a93caa0&gt;, '__doc__': '\xe6\x89\x80\xe6\x9c\x89\xe5\x91\x98\xe5\xb7\xa5\xe7\x9a\x84\xe5\x9f\xba\xe7\xb1\xbb', '__init__': &lt;function __init__ at 0x10a939578&gt;}
</pre>
<hr>
<h2>python对象销毁(垃圾回收)</h2>
<p>
Python 使用了引用计数这一简单技术来跟踪和回收垃圾。</p>
在 Python 内部记录着所有使用中的对象各有多少引用。</p><p>
一个内部跟踪变量，称为一个引用计数器。</p><p>
当对象被创建时， 就创建了一个引用计数， 当这个对象不再需要时， 
也就是说， 这个对象的引用计数变为0 时， 它被垃圾回收。但是回收不是"立即"的，
由解释器在适当的时机，将垃圾对象占用的内存空间回收。</p>
<pre>
a = 40      # 创建对象  &lt;40&gt;
b = a       # 增加引用， &lt;40&gt; 的计数
c = [b]     # 增加引用.  &lt;40&gt; 的计数

del a       # 减少引用 &lt;40&gt; 的计数
b = 100     # 减少引用 &lt;40&gt; 的计数
c[0] = -1   # 减少引用 &lt;40&gt; 的计数
</pre>
 <p>垃圾回收机制不仅针对引用计数为0的对象，同样也可以处理循环引用的情况。循环引用指的是，两个对象相互引用，但是没有其他变量引用他们。这种情况下，仅使用引用计数是不够的。Python 的垃圾收集器实际上是一个引用计数器和一个循环垃圾收集器。作为引用计数的补充， 垃圾收集器也会留心被分配的总量很大（即未通过引用计数销毁的那些）的对象。 在这种情况下， 解释器会暂停下来， 试图清理所有未引用的循环。
 </p>
 
<h3>实例</h3>
<p>析构函数 __del__ ，__del__在对象销毁的时候被调用，当对象不再被使用时，__del__方法运行：
</p>
<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">#!/usr/bin/python</span><span class="hl-code">
</span><span class="hl-comment"># -*- coding: UTF-8 -*-</span><span class="hl-code">
 
</span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Point</span><span class="hl-code">:
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">__init__</span><span class="hl-brackets">(</span><span class="hl-code"> </span><span class="hl-identifier">self</span><span class="hl-code">, </span><span class="hl-identifier">x</span><span class="hl-code">=</span><span class="hl-number">0</span><span class="hl-code">, </span><span class="hl-identifier">y</span><span class="hl-code">=</span><span class="hl-number">0</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">x</span><span class="hl-code"> = </span><span class="hl-identifier">x</span><span class="hl-code">
      </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">y</span><span class="hl-code"> = </span><span class="hl-identifier">y</span><span class="hl-code">
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">__del__</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-identifier">class_name</span><span class="hl-code"> = </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">__class__</span><span class="hl-code">.</span><span class="hl-identifier">__name__</span><span class="hl-code">
      </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-identifier">class_name</span><span class="hl-code">, </span><span class="hl-quotes">&quot;</span><span class="hl-string">销毁</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
</span><span class="hl-identifier">pt1</span><span class="hl-code"> = </span><span class="hl-identifier">Point</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">
</span><span class="hl-identifier">pt2</span><span class="hl-code"> = </span><span class="hl-identifier">pt1</span><span class="hl-code">
</span><span class="hl-identifier">pt3</span><span class="hl-code"> = </span><span class="hl-identifier">pt1</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-builtin">id</span><span class="hl-brackets">(</span><span class="hl-identifier">pt1</span><span class="hl-brackets">)</span><span class="hl-code">, </span><span class="hl-builtin">id</span><span class="hl-brackets">(</span><span class="hl-identifier">pt2</span><span class="hl-brackets">)</span><span class="hl-code">, </span><span class="hl-builtin">id</span><span class="hl-brackets">(</span><span class="hl-identifier">pt3</span><span class="hl-brackets">)</span><span class="hl-code"> </span><span class="hl-comment"># 打印对象的id</span><span class="hl-code">
</span><span class="hl-reserved">del</span><span class="hl-code"> </span><span class="hl-identifier">pt1</span><span class="hl-code">
</span><span class="hl-reserved">del</span><span class="hl-code"> </span><span class="hl-identifier">pt2</span><span class="hl-code">
</span><span class="hl-reserved">del</span><span class="hl-code"> </span><span class="hl-identifier">pt3</span></div>
</div>
</div>
<p>以上实例运行结果如下：</p>
<pre>
3083401324 3083401324 3083401324
Point 销毁
</pre>
<p>
<strong>注意：</strong>通常你需要在单独的文件中定义一个类，
</p>

<h2>类的继承</h2>
<p>面向对象的编程带来的主要好处之一是代码的重用，实现这种重用的方法之一是通过继承机制。</p>
<p>通过继承创建的新类称为<strong>子类</strong>或<strong>派生类</strong>，被继承的类称为<strong>基类</strong>、<strong>父类</strong>或<strong>超类</strong>。</p>


<p><strong>继承语法</strong>   
<pre>
class 派生类名(基类名)
    ...
</pre>
<p>在python中继承中的一些特点：</p>
<ul>
<li>1、如果在子类中需要父类的构造方法就需要显式的调用父类的构造方法，或者不重写父类的构造方法。详细说明可查看：<a href="../w3cnote/python-extends-init.html" rel="noopener noreferrer" target="_blank"> python 子类继承父类构造函数说明</a>。
</li>

<li>2、在调用基类的方法时，需要加上基类的类名前缀，且需要带上 self 参数变量。区别在于类中调用普通函数时并不需要带上 self 参数</li>

<li>3、Python 总是首先查找对应类型的方法，如果它不能在派生类中找到对应的方法，它才开始到基类中逐个查找。（先在本类中查找调用的方法，找不到才去基类中找）。</li>
</ul>
<p>如果在继承元组中列了一个以上的类，那么它就被称作"多重继承" 。</p>
<p><strong>语法：</strong></p>
<p>派生类的声明，与他们的父类类似，继承的基类列表跟在类名之后，如下所示：</p>
<pre>
class SubClassName (ParentClass1[, ParentClass2, ...]):
    ...
</pre>
<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">#!/usr/bin/python</span><span class="hl-code">
</span><span class="hl-comment"># -*- coding: UTF-8 -*-</span><span class="hl-code">
 
</span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Parent</span><span class="hl-code">:        </span><span class="hl-comment"># 定义父类</span><span class="hl-code">
   </span><span class="hl-identifier">parentAttr</span><span class="hl-code"> = </span><span class="hl-number">100</span><span class="hl-code">
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">__init__</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">调用父类构造函数</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">parentMethod</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">'</span><span class="hl-string">调用父类方法</span><span class="hl-quotes">'</span><span class="hl-code">
 
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">setAttr</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-code">, </span><span class="hl-identifier">attr</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-identifier">Parent</span><span class="hl-code">.</span><span class="hl-identifier">parentAttr</span><span class="hl-code"> = </span><span class="hl-identifier">attr</span><span class="hl-code">
 
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">getAttr</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">父类属性 :</span><span class="hl-quotes">&quot;</span><span class="hl-code">, </span><span class="hl-identifier">Parent</span><span class="hl-code">.</span><span class="hl-identifier">parentAttr</span><span class="hl-code">
 
</span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Child</span><span class="hl-brackets">(</span><span class="hl-identifier">Parent</span><span class="hl-brackets">)</span><span class="hl-code">: </span><span class="hl-comment"># 定义子类</span><span class="hl-code">
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">__init__</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">&quot;</span><span class="hl-string">调用子类构造方法</span><span class="hl-quotes">&quot;</span><span class="hl-code">
 
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">childMethod</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">'</span><span class="hl-string">调用子类方法</span><span class="hl-quotes">'</span><span class="hl-code">
 
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-identifier">Child</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">          </span><span class="hl-comment"># 实例化子类</span><span class="hl-code">
</span><span class="hl-identifier">c</span><span class="hl-code">.</span><span class="hl-identifier">childMethod</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">      </span><span class="hl-comment"># 调用子类的方法</span><span class="hl-code">
</span><span class="hl-identifier">c</span><span class="hl-code">.</span><span class="hl-identifier">parentMethod</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">     </span><span class="hl-comment"># 调用父类方法</span><span class="hl-code">
</span><span class="hl-identifier">c</span><span class="hl-code">.</span><span class="hl-identifier">setAttr</span><span class="hl-brackets">(</span><span class="hl-number">200</span><span class="hl-brackets">)</span><span class="hl-code">       </span><span class="hl-comment"># 再次调用父类的方法 - 设置属性值</span><span class="hl-code">
</span><span class="hl-identifier">c</span><span class="hl-code">.</span><span class="hl-identifier">getAttr</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">          </span><span class="hl-comment"># 再次调用父类的方法 - 获取属性值</span></div>
</div>
</div>
<p>以上代码执行结果如下：</p>
<pre>
调用子类构造方法
调用子类方法
调用父类方法
父类属性 : 200
</pre>
<p>你可以继承多个类</p>
<pre>
class A:        # 定义类 A
.....

class B:         # 定义类 B
.....

class C(A, B):   # 继承类 A 和 B
.....
</pre>
<p>你可以使用issubclass()或者isinstance()方法来检测。</p>
<ul>
<li>issubclass() - 布尔函数判断一个类是另一个类的子类或者子孙类，语法：issubclass(sub,sup)</li>
<li>isinstance(obj, Class) 布尔函数如果obj是Class类的实例对象或者是一个Class子类的实例对象则返回true。</li>
</ul>
<hr><h2>方法重写</h2>
<p>
如果你的父类方法的功能不能满足你的需求，你可以在子类重写你父类的方法：</p>
<p>实例：</p>
<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">#!/usr/bin/python</span><span class="hl-code">
</span><span class="hl-comment"># -*- coding: UTF-8 -*-</span><span class="hl-code">
 
</span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Parent</span><span class="hl-code">:        </span><span class="hl-comment"># 定义父类</span><span class="hl-code">
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">myMethod</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">'</span><span class="hl-string">调用父类方法</span><span class="hl-quotes">'</span><span class="hl-code">
 
</span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Child</span><span class="hl-brackets">(</span><span class="hl-identifier">Parent</span><span class="hl-brackets">)</span><span class="hl-code">: </span><span class="hl-comment"># 定义子类</span><span class="hl-code">
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">myMethod</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-quotes">'</span><span class="hl-string">调用子类方法</span><span class="hl-quotes">'</span><span class="hl-code">
 
</span><span class="hl-identifier">c</span><span class="hl-code"> = </span><span class="hl-identifier">Child</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">          </span><span class="hl-comment"># 子类实例</span><span class="hl-code">
</span><span class="hl-identifier">c</span><span class="hl-code">.</span><span class="hl-identifier">myMethod</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">         </span><span class="hl-comment"># 子类调用重写方法</span></div>
</div>
</div>
<p>执行以上代码输出结果如下：</p>
<pre>
调用子类方法
</pre>
<hr>
<h2>基础重载方法</h2>
<p>下表列出了一些通用的功能，你可以在自己的类重写：</p>
<table class="reference">
<tbody><tr>
<th style="width:10%">序号</th><th>方法, 描述 &amp; 简单的调用</th>
</tr>
<tr><td>1</td><td><b>__init__ ( self [,args...] )</b><br>构造函数<br>简单的调用方法: <i>obj = className(args)</i></td></tr>
<tr><td>2</td><td><b>__del__( self )</b><br>析构方法, 删除一个对象<br>简单的调用方法 : <i>del obj</i></td></tr>
<tr><td>3</td><td><b>__repr__( self )</b><br>转化为供解释器读取的形式<br>简单的调用方法 : <i>repr(obj)</i></td></tr>
<tr><td>4</td><td><b>__str__( self )</b><br> 用于将值转化为适于人阅读的形式<br>简单的调用方法 : <i>str(obj)</i></td></tr>
<tr><td>5</td><td><b>__cmp__ ( self, x )</b><br>对象比较<br>简单的调用方法 : <i>cmp(obj, x)</i></td></tr>
</tbody></table>
<hr>
<h2>运算符重载</h2>
<p>Python同样支持运算符重载，实例如下：</p>
<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">#!/usr/bin/python</span><span class="hl-code">
 
</span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">Vector</span><span class="hl-code">:
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">__init__</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-code">, </span><span class="hl-identifier">a</span><span class="hl-code">, </span><span class="hl-identifier">b</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">a</span><span class="hl-code"> = </span><span class="hl-identifier">a</span><span class="hl-code">
      </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">b</span><span class="hl-code"> = </span><span class="hl-identifier">b</span><span class="hl-code">
 
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">__str__</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-reserved">return</span><span class="hl-code"> </span><span class="hl-quotes">'</span><span class="hl-string">Vector (%d, %d)</span><span class="hl-quotes">'</span><span class="hl-code"> % </span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">a</span><span class="hl-code">, </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">b</span><span class="hl-brackets">)</span><span class="hl-code">
   
   </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">__add__</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-code">,</span><span class="hl-identifier">other</span><span class="hl-brackets">)</span><span class="hl-code">:
      </span><span class="hl-reserved">return</span><span class="hl-code"> </span><span class="hl-identifier">Vector</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">a</span><span class="hl-code"> + </span><span class="hl-identifier">other</span><span class="hl-code">.</span><span class="hl-identifier">a</span><span class="hl-code">, </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">b</span><span class="hl-code"> + </span><span class="hl-identifier">other</span><span class="hl-code">.</span><span class="hl-identifier">b</span><span class="hl-brackets">)</span><span class="hl-code">
 
</span><span class="hl-identifier">v1</span><span class="hl-code"> = </span><span class="hl-identifier">Vector</span><span class="hl-brackets">(</span><span class="hl-number">2</span><span class="hl-code">,</span><span class="hl-number">10</span><span class="hl-brackets">)</span><span class="hl-code">
</span><span class="hl-identifier">v2</span><span class="hl-code"> = </span><span class="hl-identifier">Vector</span><span class="hl-brackets">(</span><span class="hl-number">5</span><span class="hl-code">,-</span><span class="hl-number">2</span><span class="hl-brackets">)</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-identifier">v1</span><span class="hl-code"> + </span><span class="hl-identifier">v2</span></div>
</div>
</div>
<p>以上代码执行结果如下所示:</p>
<pre>
Vector(7,8)
</pre><hr>
<h2>类属性与方法</h2>
<h3>类的私有属性</h3>
<p><strong>__private_attrs</strong>：两个下划线开头，声明该属性为私有，不能在类的外部被使用或直接访问。在类内部的方法中使用时 <strong>self.__private_attrs</strong>。</p>
<h3>类的方法</h3>
<p>在类的内部，使用 <span class="marked">def</span> 关键字可以为类定义一个方法，与一般函数定义不同，类方法必须包含参数 self,且为第一个参数</p>


<h3>类的私有方法</h3>
<p>
<strong>__private_method</strong>：两个下划线开头，声明该方法为私有方法，不能在类的外部调用。在类的内部调用 <strong>self.__private_methods</strong>
</p>
<div class="example"> 
<h2 class="example">实例</h2> 
<div class="example_code">
<div class="hl-main"><span class="hl-comment">#!/usr/bin/python</span><span class="hl-code">
</span><span class="hl-comment"># -*- coding: UTF-8 -*-</span><span class="hl-code">
 
</span><span class="hl-reserved">class</span><span class="hl-code"> </span><span class="hl-identifier">JustCounter</span><span class="hl-code">:
    </span><span class="hl-identifier">__secretCount</span><span class="hl-code"> = </span><span class="hl-number">0</span><span class="hl-code">  </span><span class="hl-comment"># 私有变量</span><span class="hl-code">
    </span><span class="hl-identifier">publicCount</span><span class="hl-code"> = </span><span class="hl-number">0</span><span class="hl-code">    </span><span class="hl-comment"># 公开变量</span><span class="hl-code">
 
    </span><span class="hl-reserved">def</span><span class="hl-code"> </span><span class="hl-identifier">count</span><span class="hl-brackets">(</span><span class="hl-identifier">self</span><span class="hl-brackets">)</span><span class="hl-code">:
        </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">__secretCount</span><span class="hl-code"> += </span><span class="hl-number">1</span><span class="hl-code">
        </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">publicCount</span><span class="hl-code"> += </span><span class="hl-number">1</span><span class="hl-code">
        </span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-identifier">self</span><span class="hl-code">.</span><span class="hl-identifier">__secretCount</span><span class="hl-code">
 
</span><span class="hl-identifier">counter</span><span class="hl-code"> = </span><span class="hl-identifier">JustCounter</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">
</span><span class="hl-identifier">counter</span><span class="hl-code">.</span><span class="hl-identifier">count</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">
</span><span class="hl-identifier">counter</span><span class="hl-code">.</span><span class="hl-identifier">count</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-identifier">counter</span><span class="hl-code">.</span><span class="hl-identifier">publicCount</span><span class="hl-code">
</span><span class="hl-reserved">print</span><span class="hl-code"> </span><span class="hl-identifier">counter</span><span class="hl-code">.</span><span class="hl-identifier">__secretCount</span><span class="hl-code">  </span><span class="hl-comment"># 报错，实例不能访问私有变量</span></div>
</div>
</div>
<p>Python 通过改变名称来包含类名:</p>
<pre>
1
2
2
Traceback (most recent call last):
  File "test.py", line 17, in &lt;module&gt;
    print counter.__secretCount  # 报错，实例不能访问私有变量
AttributeError: JustCounter instance has no attribute '__secretCount'
</pre>
<p>Python不允许实例化的类访问私有数据，但你可以使用 <span class="marked">object._className__attrName</span>（ <strong>对象名._类名__私有属性名</strong> ）访问属性，参考以下实例：</p>
<pre>
#!/usr/bin/python
# -*- coding: UTF-8 -*-

class Runoob:
    __site = "www.runoob.com"

runoob = Runoob()
print runoob._Runoob__site
</pre>
<p>执行以上代码，执行结果如下：</p>
<pre>
www.runoob.com
</pre>
<h3>单下划线、双下划线、头尾双下划线说明：</h3>
<ul><li>
<p><strong>__foo__</strong>: 定义的是特殊方法，一般是系统定义名字 ，类似 <span class="marked">__init__()</span> 之类的。</p></li><li>

<p><strong>_foo</strong>: 以单下划线开头的表示的是 protected 类型的变量，即保护类型只能允许其本身与子类进行访问，不能用于 <span class="marked">from module import *</span></p>
</li><li>
<p><strong>__foo</strong>: 双下划线的表示的是私有类型(private)的变量, 只能是允许这个类本身进行访问了。</p>

</li></ul>			<!-- 其他扩展 -->
						
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	<ol class="commentlist">
		<li class="comment even thread-even depth-1" id="comment-11392"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;HaiYan</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;tan***yan@kaizegf.com</p></div><div id="runoobvote-id-11392" data-commid = "11392" class="upvotejs"><a class="upvote"></a> <span class="count">32</span></div></div><div class="comt-main" id="div-comment-11392"><p><strong>object._className__attrName</strong> 实例及解析</p>
<pre>
#!/usr/bin/python
# -*- coding: UTF-8 -*-

class JustCounter:
    __secretCount = 0  # 私有变量
    publicCount = 0    # 公开变量
    def count(self):
        self.__secretCount += 1
        self.publicCount += 1
        print self.__secretCount
    def count2(self):
        print self.__secretCount

counter = JustCounter()
counter.count()
# 在类的对象生成后,调用含有类私有属性的函数时就可以使用到私有属性.
counter.count()
#第二次同样可以.
print counter.publicCount
print counter._JustCounter__secretCount  # 不改写报错，实例不能访问私有变量
try:
    counter.count2()
except IOError:
    print "不能调用非公有属性!"
else:
    print "ok!" #现在呢!证明是滴!
</pre><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">HaiYan</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;HaiYan</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;tan***yan@kaizegf.com</p></div></span>6年前 (2017-04-26)</div></div></li><!-- #comment-## -->
<li class="comment odd alt thread-odd thread-alt depth-1" id="comment-19729"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;gongxufan</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;gon***fan@126.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="http://blog.csdn.net/qq381332153/article/details/78415338">&nbsp;&nbsp;参考地址</a></p></div><div id="runoobvote-id-19729" data-commid = "19729" class="upvotejs"><a class="upvote"></a> <span class="count">26</span></div></div><div class="comt-main" id="div-comment-19729"><p>新式类和经典类的区别：</p>
<pre>class A:
   def foo(self):
      print('called A.foo()')
class B(A):
   pass
class C(A):
   def foo(self):
      print('called C.foo()')
class D(B, C,object):
   pass

if __name__ == '__main__':
   d = D()
   d.foo()</pre>
<p>D 继承了 object 和不继承程序输出不一样，继承 object 会调用 C 类的 foo，否则会调用 Ａ 的。</p>

<p>使用 super 进行父类构造调用那么必须使用 object 继承的新式类，否则报错。</p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">gongxufan</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;gongxufan</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;gon***fan@126.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="http://blog.csdn.net/qq381332153/article/details/78415338">&nbsp;&nbsp;参考地址</a></p></div></span>6年前 (2017-11-01)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-26037"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;咕儿咕儿呱呱</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;foo***w_12@163.com</p></div><div id="runoobvote-id-26037" data-commid = "26037" class="upvotejs"><a class="upvote"></a> <span class="count">127</span></div></div><div class="comt-main" id="div-comment-26037"><p>关于类和对象总是很难理解，之前学过有个比较好理解的比喻，希望有助于理解。</p>

<p>如果我们把类比作一个建筑图纸（一张房子的蓝图），那么对象就是根据这个图纸建的实实在在的房子。而shelf则是这个房子对应的门牌，这些房子可能住着不同的人，他们需要这些门牌找到对应的家。</p>

<p>类中的属性和对象就像给这个房子设置的各种设施，一套房子建好，当然就拥有这些设施，当然你也可以根据自己的需求要不要这些设施，或者改装一下。</p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">咕儿咕儿呱呱</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;咕儿咕儿呱呱</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;foo***w_12@163.com</p></div></span>5年前 (2018-04-09)</div></div></li><!-- #comment-## -->
<li class="comment odd alt thread-odd thread-alt depth-1" id="comment-26856"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;niubaty</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;niu***y@163.com</p></div><div id="runoobvote-id-26856" data-commid = "26856" class="upvotejs"><a class="upvote"></a> <span class="count">17</span></div></div><div class="comt-main" id="div-comment-26856"><p><strong>私有方法的使用</strong></p>

<p>如下 tmp 类中，<span class="marked">__privateFun(self)</span> 为类实现的私有方法，实例化之后不可直接调用，该特点与私有变量类似不再赘述。</p>
<p><span class="marked">dir(tmp)</span> 可知该私有方法被 <strong>mapping</strong> 成 <strong>_tmp__privateFun</strong> 以防止实例直接调用。如需增加实例访问接口只需添加实例方法（例如，下面的 <strong>call_fun</strong>），在实例方法中调用私有方法即可。</p>

<pre>class tmp:
  def __init__(self):
    self.__name='hell'
    
  def __privateFun(self):
    print self.__name

  def call_fun(self):
    self.__privateFun()

t=tmp()
t.call_fun()</pre><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">niubaty</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;niubaty</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;niu***y@163.com</p></div></span>5年前 (2018-05-02)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-28629"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;David</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;hua***lc@163.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="https://www.zhihu.com/question/19754936">&nbsp;&nbsp;参考地址</a></p></div><div id="runoobvote-id-28629" data-commid = "28629" class="upvotejs"><a class="upvote"></a> <span class="count">43</span></div></div><div class="comt-main" id="div-comment-28629"><p><strong>Python 为什么要继承 object 类？</strong></p>
<p data-title="Python 为什么要继承 object 类？">继承 object 类的是新式类，不继承 object 类的是经典类，在 Python 2.7 里面新式类和经典类在多继承方面会有差异：</p>

<pre>class A:
    def foo(self):
        print('called A.foo()')

class B(A):
    pass

class C(A):
    def foo(self):
        print('called C.foo()')

class D(B, C): 
    pass

if __name__ == '__main__':
    d = D() 
    d.foo()</pre>
<p>B、C 是 A 的子类，D 多继承了 B、C 两个类，其中 C 重写了 A 中的 foo() 方法。</p>

<p>如果 A 是经典类（如上代码），当调用 D 的实例的 foo() 方法时，Python 会按照深度优先的方法去搜索 foo() ，路径是 B-A-C ，执行的是 A 中的 foo() ；</p>

<p>如果 A 是新式类，当调用 D 的实例的 foo() 方法时，Python 会按照广度优先的方法去搜索 foo() ，路径是 B-C-A ，执行的是 C 中的 foo() 。</p>

<p>因为 D 是直接继承 C 的，从逻辑上说，执行 C 中的 foo() 更加合理，因此新式类对多继承的处理更为合乎逻辑。</p>

<p>在 Python 3.x 中的新式类貌似已经兼容了经典类，无论 A 是否继承 object 类， D 实例中的 foo() 都会执行 C 中的 foo() 。但是在 Python 2.7 中这种差异仍然存在，因此还是推荐使用新式类，要继承 object 类。</p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="../note/28629">David</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;David</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;hua***lc@163.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="https://www.zhihu.com/question/19754936">&nbsp;&nbsp;参考地址</a></p></div></span>5年前 (2018-06-22)</div></div></li><!-- #comment-## -->
<li class="comment odd alt thread-odd thread-alt depth-1" id="comment-29684"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;Sonnet</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;gra***nnet@qq.com</p></div><div id="runoobvote-id-29684" data-commid = "29684" class="upvotejs"><a class="upvote"></a> <span class="count">31</span></div></div><div class="comt-main" id="div-comment-29684"><p>当你创建一个对象并给它赋一个变量的时候，这个变量仅仅引用那个对象，而不是表示那个对象本身！也就是说，变量名只是指向计算机中存储那个对象的内存。这被称作名称到对象的绑定。</p>



<pre>#!/usr/bin/python
#-*- coding=utf-8 -*-

print '-----------简单的赋值-----------'
shoplist = ['apple','mango','carrot','banana']
mylist = shoplist # 简单的赋值 只是引用变量名

del shoplist[0]
del mylist[0]

print 'shoplist 列表：',shoplist
print 'mylist 列表：',mylist

print '完整切片是真正的复制：'

mylist = shoplist[:]

del mylist[0]

print 'shoplist 列表：',shoplist
print 'mylist 列表：',mylist</pre>

<p>输出结果为：</p>

<pre>-----------简单的赋值-----------
shoplist 列表： ['carrot', 'banana']
mylist 列表： ['carrot', 'banana']
完整切片是真正的复制：
shoplist 列表： ['carrot', 'banana']
mylist 列表： ['banana']</pre>

<p>很明显，普通引用只是名称的绑定，而只有完整切片才是真正意义上的复制。所以我们在简单引用后一定要考虑是否可以更改，因为操作可能影响到源对象。</p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">Sonnet</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;Sonnet</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;gra***nnet@qq.com</p></div></span>5年前 (2018-07-16)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-33757"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;公羽黎昕</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;306***276@qq.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="https://www.cnblogs.com/blackmatrix/p/5614327.html">&nbsp;&nbsp;参考地址</a></p></div><div id="runoobvote-id-33757" data-commid = "33757" class="upvotejs"><a class="upvote"></a> <span class="count">19</span></div></div><div class="comt-main" id="div-comment-33757"><p>Python 的类和类实例都是可变对象，可以随时给属性赋值，并且在原处修改。</p>

<p>在对类属性进行修改时需要特别小心，因为所有的类实例都继承共享类属性，除非实例本身存在和类属性同名的属性。对类属性进行修改，会影响到所有由这个类生成的实例。</p>

<pre>class CA(object):

    cls_pre = 'aaaaa'

    def __init__(self):
        self.obj_pre = 'bbbbb'

a = CA()
b = CA()

print(a.cls_pre, a.obj_pre)
print(b.cls_pre, b.obj_pre)

CA.cls_pre = 'ccccc'
c = CA()

d = CA()
d.cls_pre = 'ddddd'

print(a.cls_pre, a.obj_pre)
print(b.cls_pre, b.obj_pre)
print(c.cls_pre, c.obj_pre)
print(d.cls_pre, d.obj_pre)</pre>
<p>运行结果：</p>

<pre>aaaaa bbbbb
aaaaa bbbbb
ccccc bbbbb
ccccc bbbbb
ccccc bbbbb
ddddd bbbbb</pre>
<p>代码中，将类属性 CA.cls_pre 重新赋值为 'ccccc'。在修改类属性之后，不仅是后续创建的类实例 c 的 cls_pre 发生变化，在修改类属性之前的创建的类实例 a、b 的类属性 cls_pre 都发生了变化。</p>

<p>所以，当在class语句外修改类属性时，会导致所有由这个类创建的实例的类属性都随之变化，因为所有的实例都共享类属性 CA.cls_pre。除非实例本身有同名的实例属性对类属性进行了覆盖，比如代码中的 d.cls_pre = 'ddddd'。</p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">公羽黎昕</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;公羽黎昕</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;306***276@qq.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="https://www.cnblogs.com/blackmatrix/p/5614327.html">&nbsp;&nbsp;参考地址</a></p></div></span>5年前 (2018-08-08)</div></div></li><!-- #comment-## -->
<li class="comment byuser comment-author-tianqixin bypostauthor odd alt thread-odd thread-alt depth-1" id="comment-37306"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;FS</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;429***f0967@qq.com</p></div><div id="runoobvote-id-37306" data-commid = "37306" class="upvotejs"><a class="upvote"></a> <span class="count">150</span></div></div><div class="comt-main" id="div-comment-37306"><p><img src="//www.runoob.com/wp-content/uploads/2013/12/oopxxx.png"></p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">FS</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;FS</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;429***f0967@qq.com</p></div></span>4年前 (2018-11-22)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-41154"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;黄氏面包王</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;135***6796@qq.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="https://blog.csdn.net/a984120978/article/details/81160958">&nbsp;&nbsp;参考地址</a></p></div><div id="runoobvote-id-41154" data-commid = "41154" class="upvotejs"><a class="upvote"></a> <span class="count">25</span></div></div><div class="comt-main" id="div-comment-41154">
<p data-title="Python __str__() 方法">定义 <span class="marked">__str__()</span> 方法:</p>
<pre>class Cat:
    """定义一个猫类"""
 
    def __init__(self, new_name, new_age):
        """在创建完对象之后 会自动调用, 它完成对象的初始化的功能"""
        # self.name = "汤姆"
        # self.age = 20
        self.name = new_name
        self.age = new_age  # 它是一个对象中的属性,在对象中存储,即只要这个对象还存在,那么这个变量就可以使用
        # num = 100  # 它是一个局部变量,当这个函数执行完之后,这个变量的空间就没有了,因此其他方法不能使用这个变量
 
    def __str__(self):
        """返回一个对象的描述信息"""
        # print(num)
        return "名字是:%s , 年龄是:%d" % (self.name, self.age)
 
    def eat(self):
        print("%s在吃鱼...." % self.name)
 
    def drink(self):
        print("%s在喝可乐..." % self.name)
 
    def introduce(self):
        # print("名字是:%s, 年龄是:%d" % (汤姆的名字, 汤姆的年龄))
        # print("名字是:%s, 年龄是:%d" % (tom.name, tom.age))
        print("名字是:%s, 年龄是:%d" % (self.name, self.age))
 
# 创建了一个对象
tom = Cat("汤姆", 30)
print(tom)</pre>

<p><strong>总结:</strong></p>
<ul><li>在python中方法名如果是<code>__xxxx__()</code>的，那么就有特殊的功能，因此叫做“魔法”方法</li>
<li>当使用print输出对象的时候，只要自己定义了<code>__str__(self)</code>方法，那么就会打印从在这个方法中return的数据</li>
<li><code>__str__</code>方法需要返回一个字符串，当做这个对象的描写</li>
</ul><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="../note/41154">黄氏面包王</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;黄氏面包王</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;135***6796@qq.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="https://blog.csdn.net/a984120978/article/details/81160958">&nbsp;&nbsp;参考地址</a></p></div></span>4年前 (2019-03-24)</div></div></li><!-- #comment-## -->
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					<div class="comt-tips"><input type='hidden' name='comment_post_ID' value='4558' id='comment_post_ID' />
<input type='hidden' name='comment_parent' id='comment_parent' value='0' />
</div>
					<button type="submit" name="submit" id="submit" tabindex="5"><i class="fa fa-pencil" aria-hidden="true"></i> 分享笔记</button>
				</div>
			</div>
		
				
					<div class="comt-comterinfo"> 
						<ul id="comment-author-info">
							<li class="form-inline"><label class="hide" for="author">昵称</label><input class="ipt" type="text" name="author" id="author" value="" tabindex="2" placeholder="昵称"><span class="text-muted">昵称 (必填)</span></li>
							<li class="form-inline"><label class="hide" for="email">邮箱</label><input class="ipt" type="text" name="email" id="email" value="" tabindex="3" placeholder="邮箱"><span class="text-muted">邮箱 (必填)</span></li>
							<li class="form-inline"><label class="hide" for="url">引用地址</label><input class="ipt" type="text" name="url" id="url" value="" tabindex="4" placeholder="引用地址"><span class="text-muted">引用地址</span></li>
						</ul>
					</div>
				
			
		</div>

	</form>
	</div>
<script type="text/javascript">
$(function() {
	//初始化编辑器
	
	var editor = new Simditor({
	  textarea: $('#mded'),
	  placeholder: '写笔记...',
	  upload:false,
	 // upload: {url:'/api/comment_upload_file.php',params: null,fileKey: 'upload_file',connectionCount: 1,leaveConfirm: '文件正在上传，您确定离开?'},
	  defaultImage: 'https://www.runoob.com/images/logo.png',
	  codeLanguages: '',
	  autosave: 'editor-content',
	  toolbar: [  'bold','code','ul','ol','image' ]
	});
	editor.on('selectionchanged', function() {
		$(".code-popover").hide();
	});

	// 提交数据
	$("#share_code").click(function() {
		$(".comment-signarea").hide();
		$("#commentform").show();
		
	});
	$("#user_add_note").click(function() {
		$(".comment-signarea").hide();
		$("#commentform").show();
		$('html, body').animate({
       	    scrollTop: $("#respond").offset().top
    	}, 200);
	});

	// 提交笔记
	var commentform=$('#commentform');
	commentform.prepend('<div id="comment-status" style="display:none;" ></div>');
	var statusdiv=$('#comment-status');
	
	commentform.submit(function(e){
		e.preventDefault();
		var noteContent = editor.getValue();
		// console.log(noteContent);
		noteContent = noteContent.replace(/<pre><code>/g,"<pre>");
		noteContent = noteContent.replace(/<\/code><\/pre>/g,"</pre>");
		
		// 系列化表单数据
		var comment_parent = 0;
		var is_user_logged_in = $("#is_user_logged_in").val();
		var comment_post_ID =  4558;
		var _wp_unfiltered_html_comment = $("#_wp_unfiltered_html_comment").val();
		var comment = noteContent;
		var author = $("#author").val();
		var url = $("#url").val();
		var email = $("#email").val();
		if(isBlank(author) && is_user_logged_in==0) {
			statusdiv.html('<p  class="ajax-error">请输入昵称！</p>').show();
		} else if(isBlank(email)  && is_user_logged_in==0) {
			statusdiv.html('<p  class="ajax-error">请输入邮箱！</p>').show();
		} else {
			// var formdata=commentform.serialize() + "&comment=" + noteContent ;
			// 添加状态信息
			statusdiv.html('<p>Processing...</p>').show();
			// 获取表单提交地址
			var formurl=commentform.attr('action');
			
			// 异步提交
			$.ajax({
					type: 'post',
					url: formurl,
					dataType:'json',
					data: {"comment_parent":comment_parent,"comment_post_ID":comment_post_ID, "_wp_unfiltered_html_comment":_wp_unfiltered_html_comment,"comment":comment,"url":url, "email":email,"author":author},
					error: function(XMLHttpRequest, textStatus, errorThrown){
					statusdiv.html('<p class="ajax-error" >数据不完整或表单提交太快了！</p>').show();
				},
				success: function(data, textStatus){
					if(data.errorno=="0") {
						$("#submit").prop('disabled', true);
						statusdiv.html('<p class="ajax-success" >笔记已提交审核，感谢分享笔记！</p>').show();
						alert('笔记已提交审核，感谢分享笔记！');
					}else{
						statusdiv.html('<p class="ajax-error" >'+data.msg+'</p>').show();
					}
					commentform.find('textarea[name=comment]').val('');
				}
			});
			setTimeout(function(){
		        $("#submit").prop('disabled', false);
		    }, 10*1000);
		}
		return false;

	});
	$(".comt-author").click(function() {
		href = $(this).children("a").attr("href");
		if(href.indexOf("/note/")!=-1) {
			var win = window.open(href, '_blank');
  			win.focus();
		}
	});
	$(".comt-meta span").hover(function(){
		$(this).children(".tooltip").css({ "opacity": 1, "pointer-events": "auto"});
	},function(){
		$(this).children(".tooltip").removeAttr("style");
	});
	/*
	$(".wrapper i").hover(function(){
		$(this).siblings(".tooltip").css({ "opacity": 1, "pointer-events": "auto"});
	},function(){
		$(this).siblings(".tooltip").css({ "opacity": 0, "pointer-events": "auto"});
	});
	*/
	//Upvote.create('runoobvote-id', {callback: vote_callback});
	var ajaxurl = 'https://www.runoob.com/wp-admin/admin-ajax.php';
	var callback = function(data) {
		//console.log($('#runoobvote-id').upvote('upvoted'));
		//console.log($('#runoobvote-id').upvote('downvoted'));
		//console.log(data);
		_vote_action = data.action;
		id_arr = data.id.split('-');
		um_id= id_arr[2];
		//console.log(um_id);
		
		var re = /^[1-9]+/;
		if (re.test(um_id)) { 
			var ajax_data = {
				_vote_action: _vote_action,
				action: "pinglun_zan",
				um_id: um_id,
				um_action: "ding"
			};
			//console.log(ajax_data);
			$.post(ajaxurl,ajax_data,function(status){
				//if(status.vote_num>999) {
				//	_voteHtml = '<span style="display: block; text-align: center;font-size: 20px; color: #6a737c; margin: 8px 0;">'+kFormatter(status.vote_num) +'</span>';
				//	$("#runoobvote-id-" + um_id + " .count").hide().after(_voteHtml);
				//}
				
			});
		}
	};
	if($('#comments').length && $('.upvotejs').length){
		$('.upvotejs').upvote({id: 4558, callback: callback});
	
		$.post(ajaxurl,{"action":"pinglun_zan","postid":4558},function(data){  
			$(data).each(function(key,value) {
				$("#runoobvote-id-" + value.commid + " .upvote").addClass(value.upvotejs_class);
				$("#runoobvote-id-" + value.commid + " .downvote").addClass(value.downvote_class);
				$("#runoobvote-id-" + value.commid + " .count").text(value.upvote_count);
			})
		},'json');
		
	}
	
	
});
function isBlank(str) {
    return (!str || /^\s*$/.test(str));
}
function kFormatter(num) {
	// return num;
    return Math.abs(num) > 999 ? Math.sign(num)*((Math.abs(num)/1000).toFixed(1)) + 'k' : Math.sign(num)*Math.abs(num)
}

</script>

<link rel="stylesheet" href="../0/qa.css?1.44">
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